1. Field of the Invention
The present invention relates generally to a method and apparatus for conditioning the floor of a poultry rearing facility for reuse, and more specifically, a method and apparatus for disintegrating caked and compacted material covering the floor, so-called poultry litter, following the grow-out of a flock of poultry broilers.
2. Discussion of the Related Art
In the rearing of poultry, particularly broiler chickens, the poultry are generally housed in shelters having a roof and a floor formed of compacted and leveled earth including a covering of material, e.g., an organic material such as wood sawdust, wood shavings, or rice hulls. The floor covering material is provided to absorb dropping and moisture and to insulate small chicks from cold and dampness of a bare floor. The shelters can typically be 650 feet long and 40 feet wide.
Such shelters, especially in the southern states where below freezing temperatures are rare, typically have open sides. It is customary to provide such shelters with roll-down curtains to cover the open sides, especially when there is rain accompanied by wind, to both protect the poultry and to prevent excessive wetting of the floor of the rearing area.
The floor covering material typically has a depth of perhaps several inches. Of the various organic materials used in the past, sawdust is found to be the most satisfactory because of its ability to absorb moisture from the poultry droppings, thereby causing them to dry reasonably quickly, and because it also has the ability to surface dry quite quickly if the sawdust becomes wet from rain or spilled drinking water. Another reason for using sawdust is that the sawdust provides a relatively soft cover on the earth floor and can be scraped from the floor to clean the chicken house.
After several weeks, usually seven to eight weeks, as the grow-out of the poultry progresses, the organic floor covering material becomes caked and compacted with droppings and other moisture. This caked material, so-called poultry litter, must be eliminated or reconditioned so that the floor can be reused for another flock of poultry.
In the past, when sawdust was inexpensive and available, the sawdust and caked droppings would be scraped off, for example, with a bulldozer-type scraper blade and the scraped material would simply be pushed to one end of the chicken rearing area and hauled away, and a new layer of fresh sawdust was then spread on the floor. However, sawdust is now quite expensive and frequently unavailable because of its extensive use in the manufacture of other items. Moreover, disposal of the litter can be inconvenient if the disposal sites are removed from the poultry rearing area. Accordingly, the previous technique of simply scraping the spent litter from the floor together with the droppings is no longer economical, and is frequently not possible because of the unavailability of replacement sawdust.
Instead of simply scraping the sawdust from the floor, a variety of devices have been designed for reconditioning the organic floor covering material for reuse. In order for the material to air out and dry out, the caked and moist material must be pulverized and thoroughly mixed and fluffed to allow air to circulate through and around it to remove moisture and ammonia.
U.S. Pat. No. 4,619,412 discloses a tractor-drawn machine that reduces the hardened layer of litter or organic floor covering material on the floor of a poultry house to a somewhat pulverized state so that it may be reused on the floor. A leading scraper blade of the machine slightly elevates the hardened litter layer and as the hardened litter layer traverses grid plates immediately behind the scraper blade, it is acted upon by rotating flail hammers having chopping heads. The somewhat pulverized material is discharged at the rear of the traveling machine and is deposited back onto the floor of the poultry house.
U.S. Pat. No. 4,708,294 discloses another device having a frame adapted to be moved along the floor to be conditioned including a scraper blade that scrapes litter from the floor into the path of a power driven rotary pulverizer having 29 hammers pivotally connected about a 60 inch drum for pivotal movement circumferentially of the drum. In addition, the hammer elements have flat heads.
In both of the disclosed devices, the litter falls to the floor after its first contact with the rotating hammer elements. Because of this, the litter has a tendency to break off in large chunks, thereby requiring several passes by the reconditioning devices disclosed. Additionally, because the hammers disclosed have flat heads, the hammer elements tend to cake up and require cleaning.
Further, the hammers of the commercial embodiment of U.S. Pat. No. 4,708,294 are only five inches long. After several flocks of poultry have been raised, the litter can reach a depth of up to six inches. This depth cannot be handled by the machine with only five inch long hammers.